Abnormalities in lymphocyte populations in infants with neural crest cardiovascular defects

The DiGeorge syndrome has been associated with various immune deficits. Embryologically, defects of the neural crest are associated with conotruncal and aortic arch abnormalities. The objective of this study was to determine if children with neural crest congenital heart defects can have subtle but significant immunodeficiencies. Complete blood counts with differential counts and a standard lymphocyte immunophenotyping panel of selected monoclonal antibodies were performed on peripheral blood from 20 children with neural crest cardiac disease and 34 normal newborns. The children with cardiac disease were grouped as survivors and nonsurvivors. The mean total white blood cell count was similar for all groups, but the percent lymphocytes was significantly less in the nonsurvivors than in the survivors and normal newborns (p < 0.02). The lymphocyte subsets affected were CD2, CD3, and CD4. When the cardiac patients were compared to the normal newborns, again differences in lymphocyte subsets CD2, CD3, and CD4 were seen. When comparing nonsurvivors with survivors, the mean percentages of the CD2, CD3, and CD4 T lymphocyte markers, as well as the mean lymphocyte, B cell (CD20), and natural killer cell (CD16) percentages were all lower in the nonsurvivors. It was concluded that abnormalities in specific lymphocyte populations and their subsets may be predictors of infants at greatest risk for immunodeficiency complications. Therefore children with neural crest cardiac defects should have evaluations of lymphocyte subsets at birth and be treated as if potentially immunodeficient.